US3487528A - Valve spring compressing tool - Google Patents

Description

lark 6, 1970 w. E. sHuLTz 3,487,528

VAllVl' SIIUNG COMPRESSNG T001.

Filed Jan. 16. .1968

mf A-vy Q. @44 4f 44 554 i4 y" 4Z 1 42 A .40 42 $529.4@ f4 E d United States Patent O 3,487,528 VALVE SPRING COMPRESSING TOOL William E. Shultz, 239 N. Main St., Lombard, lll. 60148 -Filed Jan. 16, 1968, Ser. No. 698,169

Int. Cl. B25b 27/26' U.S. Cl. 29-218 10 Claims ABSTRACT F THE DISCLOSURE A tool for compressing a spring, comprising a screw threaded in a nut pivotally supporting adjustable length legs which terminate in claws to grip the spring. Further the end of the screw is secured to a slide with spacer arms terminating in jaws to engage the spring. The claws and jaws are urged together or apart by turning the screw.

This invention relates to a tool for use in compressing valve springs of the type provided in overhead valve assemblies of internal combustion engines, and more particularly a tool of this type having an operating screw threaded in a nut for movement toward and away from a pair of claws at end portions of a pair of leg members pivotally connected to said nut in straddling relation to said line of travel of the operating screw.

In accordance with the present invention a pair of jaws carried by a slide occupying a position between said leg members in leading relation to said operating screw are movable a selected distance toward and away from said claw members under control of corresponding action of said screw while the latter travels only a fractional part of said selected distance of movement of the jaws. Thus a spring confined between said jaws and said claws undergoes compression to shorten the length of the spring a distance substantially greater than the required distance of movement of the screw in completing such compression of the spring. Since the length of travel of the screw is thereby limited, the dimension of the tool measured axially of the screw is accordingly minimized whereby the tool is operable to perform its function in relatively close and inaccessible quarters.

A further object of this invention resides in the provision of means for adjusting length of the legs so as to readily accommodate a wide range of variations in the axial dimension of the spring to which the tool is applied.

It is also an important feature of this invention to provide means which will enable the jaw `members to assume selected positions lengthwise of the distance separating the leg members whereby the jaw members will automatically spread apart or move closer together in accordance with corresponding action of the leg members as required to accommodate variations in the diametrical dimension of the coils of the spring undergoing compression.

It is a further object of this invention to provide an improved tool of the character indicated which is simple and inexpensive in construction and design, and durable and efficient in its operation.

Further objects of this invention will appear in the following detailed description, taken in conjunction with the accompanying drawings, forming a part of this specifcation, and in which drawings:

FIG. 1 is a front view of a valve spring compressing tool incorporating the features of this invention and shown in operative relation to a valve spring while undergoing compression with the use of the tool.

FIG. 2 is a side view of the tool shown in FIG. 1.

FIG. 3 is a central longitudinal section through the tool as shown in FIG. l.

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FIG. 4 is a transverse section taken `along line 4-4 of FIG. 1.

FIG. 4a is a view similar to FIG. 4 showing the parts in a relatively adjusted position.

FIG. 5 is a fragmentary section taken along line 5-5 of FIG. l.

FIG. 6 is a detail perspective view of one of the movable jaws of the prese'nt valve spring compressing tool.

A tool representing an embodiment of the present invention is shown in FIG. 1 of the drawing in working application to an overhead valve and valve spring assembly of an internal combustion engine 10 wherein the portion of the valve stem 11 of a valve 12 projecting outwardly through a guide opening 13 of the engine 10 is biased toward a valve closing position under force exerted by a coil spring 14 acting in one direction against a seat 15 surrounding the opening 13 and a retainer assembly 16 carried by the stem 11. A keeper 17 seated in an annular keyway 18 provided on the outwardly exposed end portion of the stem 11 forms a stop against which the retainer assembly 16 is securely held under force applied by the spring 14.

Referring more particularly to the tool, as shown, reference numeral 19 designates an operating member in the form of an externally threaded shaft 19 which has advancing and retracting helical movement in the threaded bore of a nut 20. The area toward which the shaft 19 has advancing movement via rotation of the shaft in the nut 20 is straddled by a pair of duplicate leg members. Each of the leg members includes an inner section 21 terminating in a leading end defined by a claw 22 which is tilted slightly inwardly and rearwardly of the area between the leg members. Each of said leg members also includes an outer section 23 to which the inner section of the leg member associated therewith is detachably connected so as to locate the claw 22 in selected forwardly extending position in a selected forwardly extended position relative to the outer section 23 to which it is detachably connected. Such connection of the inner and outer sections of each leg member is established via a series of threaded openings 24 provided in the inner section 21 at selected distances apart lengthwise of the leg member for predetermined engagement with a threaded fastener or pin 25 removably positioned in an opening 26 in the outer section 23 in registry with the threaded opening 24 occupied by said pin 25. A series of openings 27 provided in the inner section 21 in alternating relation to the threaded openings 24 have selective engagement with a detent or projection 28- on the outer section 23 opposite thereto to further secure the inner and outer section of each leg member in fixed adjusted relationship according to the desired position of the claw 22 forwardly of the nut 20. Each of the outer sections 23 of the leg members have integrally formed ears 29. The ears of the outer section of one of the leg members straddle opposite faces of the nut at one side of the shaft 19 and aligned openings formed in said ears receive end portions of a pin 30 carried by the nut so as to provide a pivotal connection of said leg member with the nut via said pin 30. The ears 29 of the outer section of the other of said leg members which straddle opposite face portions of the nut at the other side of the shaft 19 have similar pivotal connection with the nut via a pivot pin 31 carried by the nut 20 and having end portions received in aligned openings formed in the ears 29 of said outer section of the latter leg member.

A secondary threaded shaft 32 having threaded engagement with an internally threaded lbore 33 extending axially rearwardly from the forward end of the shaft 19 and in reversely threaded relation to the threads of the nut 20 has a forward end portion outside the confines of the bore 33 which defines a square shank 34. A slide 35 is fixed to the shank 34 of the shaft 32 so as to span the distance between the leg members and each leg member is embraced by a fork 36 defined by an end portion of the slide facing said leg member whereby the shaft 32 and the slide are locked against rotation during turning movement of the shaft 19 while the slide is free to move toward and away from the claws during such rotation of the screw 19 to likewise move the screw toward and away from said claws. The threads of the shaft 32 are not only in reverse relation to the threads of the nut 20 but are also of Coarser pitch than the threads of the nut 20 whereby helical movement of the sha-ft 32 while advanced or retracted via rotation of the shaft 19 is at an accelerated rate in relation to corresponding travel of the shaft 19. The forks 36 not only have interengagement with the leg members embraced by said forks so as to fix the shaft 32 and the slide 35 against rotation but the surface of the slide between said forks provides a seat against which the leg member embraced thereby has engagement under influence of a spring 29a acting between each leg member and the surface of the nut 20 opposite thereto. Accordingly the leg members are yieldably held at a minimum distance apart established by the slide 35 while allowed to have limited rocking movement about the pivot pins 30 and 31 so as to permit the legs to move closer together or farther apart to accommodate variations in the ldiametrical dimension of the spring straddled thereby.

Rotation of the shaft 19 in a direction to advance the shaft 32 and the slide 35 toward the claws 22 is operative to compress the spring 14 straddled by said leg members and engaged by said claws 22, as shown in FIG. l, by means of a pair of spacer arms 38. As shown in the drawing, each spacer arm has a body portion extending lengthwise of the distance between the slide 35 and claws 22 of the leg members and said ybody portion is maintained alongside the inwardly facing surface of the inner section 21 of the leg member associated therewith through a connection between a wing 39 formed integrally with each spacer arm 38 and the slide 35. Such connection includes a stirrup member 40 fitted on the shank 35 and secured thereto by a suitable fastener 41 through which the wings 39 of said spacer arms occupy a position astride the shank 34 while confined between the stirrup member 40 and the surface of the slide 35 facing said stirrup member. Thus The spacer arms 38 have movement toward and away from the claws 22 under control of corresponding travel of the slide 35. While so undergoing movement toward and away from the claws the opposite longitudinal edges of the leg member with which each spacer arm 38 is associated are slidably engaged by flanges 42 formed along opposite longitudinal edges of the spacer arm whereby said arms 38 are kept on a course in alignment with the leg members during movement of the slide 35 toward and away from the claws 22. A jaw 43 is defined by an inwardly extending wing formed integrally with each spacer arm 38 in forwardly spaced relation to the wing 39 of the arm 38 associated therewith. The jaws 43 are at such distance apart as to allow the stem 11 of a valve 12 to be straddled thereby while the spring 14 associated with the valve occupies a position in rearward engagement with the surfaces of the jaws 43 facing the claws 22. Thus while the claws 22 have gripping engagement with a coil of the spring 14 at a distance ahead of the jaws 43, rotation of the shaft 19 in a direction to advance the Shaft 32 and slide 35 toward the claws 22 causes the jaws 43 to apply pressure to compress the spring 14 as shown in FIG. 1. The end of the operating shaft 19 extending rearwardly of the nut 20 is fitted with a suitable handle 44 so as to facilitate manipulation of the shaft 19 in conjunction with action of the tool in compressing a valve spring to which the tool is applied.

Springs 39a anchored at opposite ends thereof to pins 39b mounted in aligned openings of ears provided on the spacer arms operate to apply yieldable force along opposite sides of the space occupied by the wings 39 of the spacer arms to normally resist movement of the wings away from each other. However, these springs 39a allow the wings to spread apart as shown in FIG. 4a so as to enable the spacer arms 38 and the jaw members 43 associated therewith to assume adjusted positions lengthwise of the distance between the leg members of the tool in accordance with corresponding swinging movement of the leg members on the pivots 30 as required to accommodate variations in the diametrical dimension of the coils of the spring undergoing compression.

From the foregoing description taken in connection with the accompanying drawings it will be readily obvious that the present invention provides an improved tool for compressing valve springs which will not only furnish greater efficiency in operation than in formerly known tools of this type but affords features of adjustability to accommodate a wide range of variation in length and diameter of coil springs as well as effecting easier and faster performance in valve spring compressing jobs.

What is claimed is:

1. A valve spring compressing tool having an operating screw, a nut in which said operating screw is threaded for advancing and retracting helical movement in a `fixed path via rotation of said screw in said nut, a pair of duplicate leg members pivotally connected to said nut in straddling relation to said line of travel of the operating screw, a claw defined by an end portion of each of said leg members and facing the area between said leg members, a slide connected to said operating screw in leading relation to said screw and movable a selected distance toward and away from said claws under control of corresponding action of said screw while the latter travels only a fractional part of said selected distance of movement of said slide, and jaws carried by said slide for engagement with a Spring straddled by said claw members to compress said spring upon rotation of said screw to advance said slide in the direction of said claws while said claws have gripping engagement with a coil of said spring forwardly of the portion of the spring engaged by said jaws.

2. A valve spring compressing tool according to claim 1 wherein said slide is connected to said operating screw via a secondary shaft having screw threaded engagement with an internally threaded bore in the forward end of said operating screw, and said threads of said bore are in reverse relation to and of coarser pitch than the threads of the nut and the operating screw.

3. A valve spring compressing tool having an operating screw, a nut in which said operating screw is threaded for advancing and retracting helical movement in a fixed path via rotation of said screw in said nut, a pair of duplicate leg members pivotally connected to said nut in straddling relation to said line of travel 0f the operating screw, a claw defined by an end portion of said leg members and facing the area between said leg members, a slide connected to said operating screw in leading relation to said screw and movable toward and away from said claws under control of corresponding action of said screw, and jaws adjustably carried by said slide for engagement with a spring straddled by said claw members to compress said spring upon rotation of said screw to advance said slide in the direction of said claws while said claws have gripping engagement with a coil of said spring forwardly of the portion of the spring engaged by said jaws, said jaws being shiftable toward and away from each other in accordance with movement of said leg members toward and away from each other.

4. A valve spring compressing tool according to claim 3 wherein means are provided for yieldably resisting movement of said jaws away from each other.

v5. A valve spring compressing tool according to claim 3 wherein said claw defined by an end portion of said leg members includes a first section of each of Said leg members, and the portion of each leg member pivotally connected to said nut includes a second section to which the rst section of the leg member associated therewith is locked with the 'first section in selective extended positions lengthwise of the second section.

6. A valve spring compressing tool according to claim 3 wherein each of said jaws is defined by a spacer member extending along the inner surface of a leg member in forwardly projecting relation to said slide.

7. A valve spring compressing tool according to claim 3 wherein each of said jaws is defined by a spacer member extending along the inner surface of a leg member in forwardly projecting relation to said slide and each of said spacer members have outwardly extending flanges which occupy positions astride the opposite longitudinally extending edges of the leg member associated therewith.

8. A valve spring compressing tool according to claim 3 wherein said slide is movable a selected distance to ward and away from said claws under control of corresponding action of said screw while the latter travels only a fractional part of said selected distance of move- 'ment of said slide.

9. A valve spring compressing tool according to claim 3 wherein said slide is connected to said Operating screw via a secondary shaft having screw threaded engagement with an internally threaded bore in the forward end of said operating screw, and said threads of said bore are References Cited UNITED STATES PATENTS- 1,041,419 10/ 1912 Borden 29-261 X 1,425,796 8/ 1922 Salsgiver 29-217 2,566,460 9/1951 Mihalic 29--217 FOREIGN PATENTS `812,016 4/ 1959 Great Britain.

ROBERT C. RIORDON, Primary Examiner I. C. PETERS, Assistant Examiner U.S. C1. X.R. 29-261

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